1. Technical Field of the Invention
The present invention relates to novel topically applicable cosmetic/dermatological compositions for the UV-photoprotection of human skin and/or hair against the damaging effects of UV-photoprotection, in particular solar radiation, and to the use of same for the aforesaid cosmetic/dermatological indications.
This invention more specifically relates to topically applicable UV-A and/or UV-B sunscreen compositions, most notably alcoholic sunscreen gels, that are waterproof, have pleasant aesthetics and, characteristically, exhibit virtually no pilling. The subject compositions are well suited as “sport” products and comprise an effective non-pilling amount of a tetrapolymer of methacrylic acid, methyl methacrylate, butyl acrylate and cetyl-eicosinyl methacrylate.
2. Description of the Prior Art
It is well known to this art that light radiation of wavelengths of from 280 nm to 400 nm promotes tanning of the human epidermis, and that irradiation of wavelengths of from 280 nm to 320 nm, i.e., UV-B irradiation, causes erythema and burning of the skin which can impair the development of a natural tan; hence, such UV-B radiation must thus be screened from the skin.
It is also known to this art that UV-A radiation, of wavelengths from 320 to 400 nm, which tans the skin, also adversely affects it, in particular in the case of sensitive skin or a skin which is continually exposed to solar radiation.
UV-A rays cause, in particular a loss in the elasticity of the skin and the appearance of wrinkles, promoting a premature aging thereof. Such irradiation promotes triggering of the erythematous reaction or enhances this reaction in certain individuals, and may even be the source of phototoxic or photoallergic reactions. Thus, it is desirable to also screen our UV-A radiation.
A wide variety of cosmetic compositions intended for the photoprotection (UV-A and/or UV-B) of human skin is known to this art.
These photoprotective/sunscreen compositions are quite often oil-in-water emulsions (namely, a cosmetically acceptable vehicle, carrier or diluent comprising an aqueous continuous dispersing phase and an oily discontinuous dispersed phase) which contains, in various concentrations, one or more standard lipophilic and/or hydrophilic organic sunscreen compounds capable of selectively absorbing harmful or deleterious UV radiation. These sunscreen compounds (and the amounts thereof) are selected as a function of the desired sun protection factor (the sun protection factor (SPF) being expressed mathematically by the ratio of the irradiation time required to attain the erythema-forming threshold with the UV screening agent to the time required to attain the erythema-forming threshold in the absence of UV screening agent).
Alcohol based sunscreen gel compositions are ideal for sport applications because they are fast drying and non-greasy. Polymeric film-formers are incorporated into these formulations to ensure even coverage of the sunscreens and to assist in rendering the formulation water resistant. Nonetheless, many of the common film-forming polymers included in sunscreen formations are not soluble in ethanol (such as PVP/Eicosene copolymer).
Indeed, the standard film-former employed in ethanol based sunscreen products is Dermacryl® LT marketed by National Starch & Chemical Company (INCI Name: acrylates/octylacrylamide copolymner). This polymer is easily solubilized in ethanol, but a major drawback of this polymer is that it rubs off the skin during product application, leaving the polymer residue in clumps of small balls or the like, resembling pills, on the skin (“pilling”). This is aesthetically unattractive, and may reduce or eliminate the function of the film-former.
Too, it is believed that all other film-formers to date included in alcohol based sunscreen formulations produce pilling during application of the product.
Dermacryl® LT (CAS Number: 80570-62-3), for example, is a hydrophobic, high molecular weight carboxylated acrylic copolymer. It functions as a film-former in a broad range of cosmetic formulations, imparting waterproofing, increased occlusivity and decreased rub-off of actives. Unlike traditional film-formers used in skin care, Dermacryl® LT is said to have been specifically designed to provide the performance benefits of a film-former without leaving the characteristic tactile properties. It is a fine, white, free-flowing powder, essentially free of foreign material: % volatiles—3.0 maximum; acidity—2.20 to 2.70 meq/g.
A number of Dermacryl® LT sunscreen compositions is commercially available from National Starch & Chemical. These include:
Daily UV Protection Cream (SPF ≈ 16)IngredientsINCI Designation% W/WSupplierPhase ANeo Heliopan AVOctyl7.50HaarmannMethoxycinnamate& ReimerMyrj 52SPEG-40 Stearate1.00UniqemaCerasynt QGlyceryl2.00Van DykStearate SECetyl AlcoholCetyl Alcohol1.00Emersol 132Stearic Acid T.P.3.00EmeryTioveil FINTitanium Dioxide/1.70TioxideC12–15Alkyl BenzoateFinsolv TNC12–15 Alkyl5.00FinetexBenzoateDC 344 FluidCyclomethicone3.00Dow CorningDC 556 FluidPhenyl1.00Dow CorningTrimethiconeAbil B8852Dimethicone1.00GoldschmidtCopolyolPhase BDeionized WaterWater (Aqua)32.80Triethanolamine (99%)Triethanolamine4.00DowDermacryl LTAcrylates/1.00NationalOctylacrylamideStarchCopolymerNeo Heliopan Hydro2-4.00H&RPhenylbenzimidazole-5-Sulfonic AcidCarbopol 940Carbomer25.00B.F.(2% Aq. Soln.)GoodrichPhase CPropylene GlycolPropylene Glycol3.00Dry-Flo PCAluminum Starch3.00NationalOctenylsuccinateStarchPhase DGermaben IIEPropylene1.00SuttonGlycol (and)LabsDiazolidinyl Urea(and) Methylparaben(and) Propylparaben100.00
This product (supplier designation 7528-149A) is formulated as follows:    Phase B: Combine Triethanolamine (99%) and Deionized Water, heat to 60° C. Slowly sift in Dermacryl LT heat to 80° C. When complete, sift in Neo Heliopan Hydro and Carbopol 940, mix until complete.    Phase A: Combine and heat to 80° C. Add Phase A to Phase B at 80° C., mix for 15–30 minutes. Cool to 40° C. Slurry Dry-Flo PC in Propylene Glycol, add to Phase A and Phase B at 40° C., mix thoroughly. Add Phase D. Cool to room temperature and package.
Daily UV Protection Lotion (SPF ≈ 18)IngredientsINCI Designation% W/WSupplierPhase ANeo Heliopan AVOctyl7.50HaarmannMethoxycinnamate& ReimerBrij 76Stearate 101.00UniqemaCerasynt QGlyceryl1.50Van DykStearate SECetyl AlcoholCetyl Alcohol1.00Emersol 132Stearic Acid T.P.1.50EmeryTioveil FINTitanium Dioxide/1.70TioxideC12–15Alkyl BenzoateFinsolv TNC12–15 Alkyl5.00FinetexBenzoateDC 344 FluidCyclomethicone3.00Dow CorningDC 556 FluidPhenyl1.00Dow CorningTrimethiconeAbil B8852Dimethicone0.50GoldschmidtCopolyolPhase BDeionized WaterWater (Aqua)40.30TriethanolamineTriethanolamine4.00Dow(99%)Dermacryl LTAcrylates/1.00NationalOctylacrylamideStarchCopolymerNeo Heliopan2-4.00H&RHydroPhenylbenzimidazole-5-Sulfonic AcidCarbopol 940Carbomer20.00B.F.(2% Aq. Soln.)GoodrichPhase CPropylene GlycolPropylene Glycol3.00Dry-Flo PCAluminum Starch3.00NationalOctenyl succinateStarchPhase DGermaben IIEPropylene1.00SuttonGlycol (and)LabsDiazolidinyl Urea(and) Methylparaben(and) Propylparaben100.00
This product (supplier designation 7528-149B) is formulated as follows:    Phase B: Combine Triethanolamine (99%) and Deionized Water, heat to 60° C. Slowly sift in Dermacryl LT heat to 80° C. When complete, sift in Neo Heliopan Hydro and Carbopol 940, mix until complete.    Phase A: Combine and heat to 80° C. Add Phase A to Phase B at 80° C., mix for 15–30 minutes. Cool to 40° C. Slurry Dry-Flo PC in Propylene Glycol, add to Phase A and Phase B at 40° C., mix thoroughly. Add Phase D. Cool to room temperature and package.
After Sun LotionIngredientsINCI Designation% W/WSupplierPhase AEmersol 132Stearic Acid T.P.2.00EmeryFinsolv TNC12–15 Alkyl Benzoate6.50FinetexFancol CBCocoa Butter1.00FanningLipovol WGOWheat Germ Oil1.00LipoVitamin ETocopheryl Acetate0.50BASFAcetate-CCerasynt SDGlyceryl Stearate2.00Van DykMyrj 52SPEG-40 Stearate1.00UniqemaPhase BDeionized WaterWater (Aqua)59.30Aloe Vera Gel 1:1Aloe Barbadensis Gel10.00Dr. MadisLabsPricerene 9088Glycerin3.00UniqemaCarbopol 940Carbomer10.00B.F.(2% Aq. Soln.)GoodrichTriethanolamineTriethanolamine1.00Dow(99%)AllantoinAllantoin0.50SuttonLabsDermacryl LTAcrylates/1.00NationalOctylacrylamideStarchCopolymerPhase CGermaben IIEPropylene Glycol (and)1.00SuttonDiazolidinyl UreaLabs(and) Methylparaben(and) PropylparabenPhase DFragranceFragrance (Perfume)0.20100.00
And this particular product (supplier designation 7661-23) is formulated as follows:    Combine Phase B, except for Dermacryl LT. Heat to 80° C. Slowly sift in Dermacryl LT, mix until complete. Combine Phase A, heat to 80° C. Add Phase A to Phase B at 80° C., mix for 30 minutes. Cool to 40° C., add Phase C and Phase D. Cool to room temperature and package.
The aforesaid phenomenon of pilling, however, remains a conspicuous disadvantage and drawback in the high SPF alcoholic sunscreen gel art.